1. Field of the Invention
This invention relates generally to the field of commercial building environmental safety and regulatory compliance and more specifically to data sensing remote units reporting building environmental conditions to a central location for logging and control.
2. Description of the Related Art
Commercial buildings such as office complexes are environmentally controlled by numerous thermostats that either activate local heating and cooling, or report to a central control location. These units, for the most part, do not measure, report, or record local environmental conditions other than temperature. Safety requirements and ever evolving governmental regulations require recording and reporting of localized environmental conditions including temperature, humidity, carbon dioxide level, toxic gases in some locations, particulate counts and other quantities.
Prior art systems exist for closed loop control of some building parameters such as temperature, and remote sensors in these systems are mostly thermostats. These thermostats are mostly bimetal, analog electronic, pneumatic, or digital. None of these systems compile or report localized environmental data for compliance with governmental or safety regulations.
What is badly needed is a remote sensor array that is reasonably priced and physically small that directly replaces existing thermostats in commercial buildings. This array must be able to measure desired parameters, while still performing the function of the thermostat it replaced. In addition, this array must couple into an inter-building communication system comprising existing thermostat wiring or building power wiring. Remote arrays must be placed at numerous locations, and must report data, on command, to a central location where similar data from other parts of the building can be logged, combined, processed, reduced, and stored for further reporting. The central logging system should be able to communicate with each of the local sensor arrays to command data and, in addition, must also be capable of communicating with a computer or telephone line to report data for compliance verification. The central logging system must store data until a local or remote computer requests it. It must be able to take commands from a computer and modify its function on such commands.